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又找到一篇关于帆的调整文章
Sheeting Angles
1. The angle between the boom and the centre line of the yacht when the sails are close hauled and the yacht is sailing at its most efficient speed to windward is called the sheeting angle. In general, the main boom is set to a relatively small angle about 5°. This means a 300 mm boom will be set about 25mm from the centreline. The jib boom must be set to a greater angle of about 10° which means a 300 mm boom will be set about 50 mm from the centreline. These values will depend on many factors including the fullness of the sail, the twist in the sail and the wind velocity but the values given should serve as a starting point. 大致意思是：sheeting angle指当艇迎着来风45度前进时帆的横杆与船体中心线的夹角，以这个夹角游艇有最有效的速度。一般主帆是5度，副帆是10度。这个角还与其它一些因素有关，包括帆的大小、帆的弯曲度、风速，但给出的数值做为初始参考角度。
2. Location of sheet attachment points on the booms is equally important. When the sail control on your transmitter is moved from its close hauled position to its fully out position the main sheet will move sufficient distance to allow the main boom to move to a position at right angles to the centreline of the yacht moving through an arc of 85°. As the jib sheet will move the exact same distance as the main sheet then if the jib boom is to move to a position at right angles it will move through an arc of only 80°. This can only occur if the attachment point for the jib sheet on the jib boom is slightly further from the pivot point then the attachment point for the main sheet from its pivot point. Typical values for the main is 220mm behind the gooseneck pivot and for the jib is 240 mm behind its pivot point.
大致意思是：两个帆从初始角度到完全打开的直角所走的路程长度是不一样的。一个是85度，一个是80度，拉绳的作用点也是不一样的。前帆作用点比主帆要稍微长一些。
3. To maintain this differential movement for the two booms, the pull from the sheet fairlead should be as horizontal as possible. This means the mainsheet post should be as close as possible to the main boom and similarly for the jib fairlead. This is really critical for the main as the amount of twist in the sail is controlled by tension in the boom vang so as the boom moves out, the twist stays much the same. Any vertical component to the mainsheet at close hauled will effectively increase the downward pull on the boom and hence to maintain twist less vang pressure is needed. As the boom moves out as in a reach, this vertical component in the main sheet rapidly reduces so the twist will increase significantly as the vang pressure is now too small and drive will decrease which is exactly what you don't want in a reach! Trying to maximise the twist for a reach when the sail is half out will mean there will be too much down force on the boom at close hauled position, reducing the twist and causing the top half of the sail to stall as the leech is pulled too tight. This situation is not quite so critical for the jib as the jib uphaul maintains the twist in the sail despite increases down tension on the jib sheet and the larger sheeting angle means the vertical component is less. Nevertheless it is still wise to keep the jib boom as close as possible to the jib sheet fairlead and maintain as horizontal a pull as possible.
这一段也与设置有关，具体看你的游艇是什么机构吧。
总之，迎风45度方向close hauled是速度最快的方向，这时的帆应该是全收紧的，留的角度也是针对45度角最佳的（包括凸起大小、攻角）。而来风直角时，帆应该能够是全90度打开（也有文章说留一定的小角度）。为了保证两个不同初始角度的帆最后都能达到一至的90度全开，就要在拉绳的作用点上再仔细调整调整。
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来自苹果客户端
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发表于 2019-10-3 23:26
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楼主
发表于 2019-10-4 18:55
